Many reference sources that used to be only in print are now available electronically. These are great places to begin research, especially if you are not very familiar with a topic. For example, an encyclopedia article can in a page or two show you the most important facts, events, people, statistics. This will help you understand more complex information you will use later.
Online reference books and electronic resources from the library will lead to more reliable information than you usually get from a web search. Here are four of the best databases to use to find information on World History.